There are different types of quarter-turn fasteners available where a one-quarter turn relative movement between fastener element will shift the assembly between a completely locked and a completely unlocked position. This is often accomplished by the use of a spiral cam slot in one of the members and a lateral cam follower in the other. The spiral cam slot is of the type where a locking detent is employed at one end of the cam slot as a retention means in the locked position. In common types of quarter-turn fasteners, such as the type where the spiral cam slot and cam follower are utilized, relative axial movement is required for the cam follower to follow the spiral cam slot along its length. To accomplish this it is common practice to utilize a separate spring member as part of the assembly either as a separate component for the stud assembly or as a resilient part of the receptacle. Naturally, additional components add to the cost of the assembly as well as adding to the complexity of the device.
It should also be kept in mind that in certain environments rigid receptacles are employed. With the requirement of a complete rigid receptacle, a resilient member has to be separately assembled with the stud and receptacle in order to achieve the necessary axial relative movement between components.
Additionally, it has been found that the cost of the fastener assembly can be greatly reduced if the need for a separate receptacle component is eliminated. In place of the separate receptacle to be mounted on one of the two members to be fastened, an appropriate opening for the stud and an appropriate cam follower in the opening can be provided on one of the members to be fastened so it is not necessary to supply an independent receptacle element. The cost of construction of the fastener assembly is accordingly much less and the cost of attaching the fastener elements to the members to be fastened is materially reduced. However, by providing the cam follower and appropriate openings in one of the members, it is difficult if not impossible to integrally include a resilient portion on the member to provide the necessary axial movement for the quarter-turn fastener. A separate resilient member would be required to complete the assembly in workable order. Naturally, the result is an increase in costs in both construction and use.
It is readily apparent that a need is present for a fastener which employs a one-piece stud arrangement of the quarter-turn type which is adaptable for use with a low cost one-piece receptacle or a receptacle which is integrally formed in one of two members to be fastened. The savings in cost of such a structure would be significant.